Parent Hydrides

R-2.3.3 Heterogeneous hydrides other than heteropolyboron hydrides

R- Monocyclic compounds with no more than 10 ring members and containing one or more heteroatoms, may be named by using the extended Hantzsch-Widman system. The name is formed by combining the "a" prefix(es) for the heteroatom(s) (Table 3) with a stem indicating the size of the ring (Table 4). The prefixes designating heteroatoms are cited in the order of their appearance in Table 3; and the heteroatoms of the structure are numbered in the same order.

Examples of Hantzsch-Widman names (R-

(Cyclohexagermane, according to R-2.3.2)

Retained trivial and semisystematic names for heteromonocyclic compounds are given in R-9.1, Table 23 and Table 24.

R- The position of a single heteroatom determines the numbering in a monocyclic compound.

Example to R-

R- When the same heteroatom occurs more than once in a ring, the numbering is chosen to give the lowest locants to the heteroatoms.

Example to R-

R- When heteroatoms of different kinds are present, the locant 1 is given to a heteroatom which appears earliest in Table 3. The numbering is then chosen to give the lowest locants to the heteroatoms, first considered as a set without regard to kind; if a choice still remains, then to a heteroatom appearing earliest in Table 3.

Examples to R-

R- Heteromonocyclic compounds may be named by replacement nomenclature. However, replacement nomenclature for heteromonocycles with 10 or fewer members has usually been applied only to silicon-containing rings. Numbering follows R-

Examples to R-

R- Saturated monocyclic systems consisting of repeating units of two different skeletal atoms may be named by citing successively the prefix "cyclo-" followed by a multiplying infix denoting the number of repeating units, the "a" terms of the atoms of the repeating unit in the reverse order to that given in R-9.3, and the suffix "-ane". The terminal letter "a" of an "a" term is elided when followed by a vowel; the terminal vowel of a numerical prefix is not elided even when the "a" term begins with the same vowel. Numbering follows, R-

Examples to R-

This HTML reproduction is as close as possible to the published version [see IUPAC, Commission on Nomenclature of Organic Chemistry. A Guide to IUPAC Nomenclature of Organic Compounds (Recommendations 1993), 1993, Blackwell Scientific publications, Copyright 1993 IUPAC]. If you need to cite these rules please quote this reference as their source.

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